/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.jdy.haoduoai.util.animation;

import android.graphics.Camera;
import android.graphics.Matrix;
import android.view.animation.Animation;
import android.view.animation.Transformation;

/**
 * An animation that rotates the view on the Y axis between two specified
 * angles. This animation also adds a translation on the Z axis (depth) to
 * improve the effect.
 */
public class Rotate3dAnimation extends Animation {
  private final float mFromDegrees;
  private final float mToDegrees;
  private final float mCenterX;
  private final float mCenterY;
  private final float mDepthZ;
  private final boolean mReverse;
  private final boolean mIsRY; // 是否绕Y轴
  private Camera mCamera;

  /**
   * Creates a new 3D rotation on the Y axis. The rotation is defined by its
   * start angle and its end angle. Both angles are in degrees. The rotation is
   * performed around a center point on the 2D space, definied by a pair of X
   * and Y coordinates, called centerX and centerY. When the animation starts, a
   * translation on the Z axis (depth) is performed. The length of the
   * translation can be specified, as well as whether the translation should be
   * reversed in time.
   * 
   * @param fromDegrees
   *          the start angle of the 3D rotation
   * @param toDegrees
   *          the end angle of the 3D rotation
   * @param centerX
   *          the X center of the 3D rotation
   * @param centerY
   *          the Y center of the 3D rotation
   * @param reverse
   *          true if the translation should be reversed, false otherwise
   */
  public Rotate3dAnimation(float fromDegrees, float toDegrees, float centerX,
      float centerY, float depthZ, boolean reverse, boolean isRY) {
    mFromDegrees = fromDegrees;
    mToDegrees = toDegrees;
    mCenterX = centerX;
    mCenterY = centerY;
    mDepthZ = depthZ;
    mReverse = reverse;
    mIsRY = isRY;
  }

  @Override
  public void initialize(int width, int height, int parentWidth,
      int parentHeight) {
    super.initialize(width, height, parentWidth, parentHeight);
    mCamera = new Camera();
  }

  @Override
  protected void applyTransformation(float interpolatedTime, Transformation t) {
    final float fromDegrees = mFromDegrees;
    float degrees = fromDegrees
        + ((mToDegrees - fromDegrees) * interpolatedTime);

    final float centerX = mCenterX;
    final float centerY = mCenterY;
    final Camera camera = mCamera;

    final Matrix matrix = t.getMatrix();

    camera.save();
    if (mReverse) {
      camera.translate(0.0f, 0.0f, mDepthZ * interpolatedTime);
    } else {
      camera.translate(0.0f, 0.0f, mDepthZ * (1.0f - interpolatedTime));
    }

    if (mIsRY) {
      camera.rotateY(degrees);
    } else {
      camera.rotateX(degrees);
    }

    camera.getMatrix(matrix);
    camera.restore();

    matrix.preTranslate(-centerX, -centerY);
    matrix.postTranslate(centerX, centerY);
  }
}
